feat: CVE conversion triager tool

[jess-lowe]

Quite often do we need to compare multiple records of one CVE record to triage conversion issues, so this tool will allow us to compare three versions at a time.

You can select from the following record locations:

• the og cve5 record
• the og NVD record
• the nvd-converted osv record in prod
• the nvd-conversion metrics notes in prod
• the nvd-converted osv record in test
• the nvd-conversion metrics notes in test
• the cve5-converted osv record in prod
• the cve5-conversion metrics notes in prod
• the cve5-converted osv record in test
• the cve5-conversion metrics notes in test
• the combined output in prod
• the combined output in test
• prod api
• test api

It currently exists at /triage, and utilises a proxy mechanism to load the records, but not as a path (as to prevent accessing unrelated parts of the bucket)

In the future could add a tool for an LLM to help triage what the actual problem is, but that's for another day

[jess-lowe]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces a new CVE conversion triager tool, which is a great addition for comparing different CVE record versions. The implementation includes a new frontend page with its corresponding JavaScript and SCSS, and a backend proxy handler in Python. The overall structure is well-thought-out. I've included several suggestions to enhance code quality, maintainability, and adherence to best practices in both the frontend and backend code.